Gardening: slugs (and snails) and copper

Self-tutoring about gardening: the tutor mentions a possible way to deter slugs and snails.

Supposedly, slugs and snails don’t like touching copper because it reacts with their slime. Therefore, a copper boundary around a garden can deter them from entering, so prevent at least some of the damage they would do.

After visiting slughelp.com, I’m not sure how convinced I am about the real efficacy of copper, but it’s probably worth experimenting in one’s own garden to find out.